U.S. patent number 4,669,492 [Application Number 06/709,305] was granted by the patent office on 1987-06-02 for cosmetic stick for a powder pencil.
This patent grant is currently assigned to Schwan-Stabilo Schwanhausser GmbH & Co.. Invention is credited to Reinhard von Kleinsorgen.
United States Patent |
4,669,492 |
von Kleinsorgen |
June 2, 1987 |
Cosmetic stick for a powder pencil
Abstract
A cosmetic stick for a powder pencil comprises a stable stick
body formed from powder base material and pigment, optionally with
binding agent, lubricant and/or adhesion-enhancing agent, together
with a particulate material which is additionally contained in the
stick body in finely divided form, the particles thereof being
harder than the base materials. The particulate material includes
at least one derivative of tricalcium phosphate, tetracalcium
phosphate or calcium pyrophosphate.
Inventors: |
von Kleinsorgen; Reinhard
(Nuremberg, DE) |
Assignee: |
Schwan-Stabilo Schwanhausser GmbH
& Co. (DE)
|
Family
ID: |
6235329 |
Appl.
No.: |
06/709,305 |
Filed: |
March 7, 1985 |
Foreign Application Priority Data
Current U.S.
Class: |
132/218; 132/318;
401/49; 424/DIG.5 |
Current CPC
Class: |
A61K
8/24 (20130101); A61Q 1/10 (20130101); Y10S
424/05 (20130101); A61K 2800/872 (20130101) |
Current International
Class: |
A61K
8/24 (20060101); A61K 8/19 (20060101); A61Q
1/10 (20060101); A61Q 1/02 (20060101); A45D
040/20 () |
Field of
Search: |
;401/49
;132/79A,79C,82A,88.7,88.5 ;424/63,64,DIG.5,57 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Apley; Richard J.
Assistant Examiner: Beaurage; Gregory
Claims
What is claimed is:
1. A cosmetic stick for a powder pencil having a stable stick body
comprising powder base material, pigment, optionally with the
addition of at least one additive material selected from the group
consisting of binding agent, lubricant and adhesive-enhancing
agent, and a particulate material in finely divided form, which
comprises particles of greater hardness than the base materials and
which includes at least one material selected from the group
consisting of tricalcium phosphate, tetracalcium phosphate, calcium
pyrophosphate and derivatives thereof.
2. A stick as set forth in claim 1 wherein said particulate
material is contained in a proportion of from substantially 5 to
40% by weight.
3. A stick as set forth in claim 2 wherein said proportion of said
particulate material is from substantially 7 to 20% by weight.
4. A stick as set forth in claim 1 wherein the particle size of
said particulate material is from 10 to 50.mu..
5. A stick as set forth in claim 1 wherein the phosphate of the
particulate material is produced by sintering hydroxyl apatite
(Ca.sub.5 (PO.sub.4).sub.3 OH).
6. A stick as set forth in claim 5 wherein the phosphate is
sintered to form porous particles.
7. A stick as set forth in claim 6 wherein after the sintering
operation said particles are from 10 to 50.mu. in grain size.
8. A stick as set forth in claim 6 wherein said porous particles
have a pore size of from 0.5 to 1.5.mu. in diameter.
9. A stick as set forth in claim 5 wherein after the sintering
operation the phosphate is ground to a grain size of from 10 to
50.mu..
10. A stick as set forth in claim 6 wherein after the sintering
operation the phosphate is ground to a grain size of 10 to
50.mu..
11. In a powder pencil having a stick body comprising a powder base
material, a pigment and a particulate material in finely divided
form comprising particles which are of greater hardness than the
base material, the improvement wherein said particulate material is
selected from the group consisting of at least one derivative of
tricalcium phosphate, tetracalcium phosphate and calcium
pyrophosphate.
12. A powder pencil as set forth in claim 11 and further including
at least one additive material selected from the group consisting
of a binding agent, a lubricant and an adhesion-enhancing
agent.
13. A powder pencil including a cosmetic stick comprising
substantially the following composition: 22% by weight of talcum,
35% by weight of mica, 15% by weight of sintered hydroxyl apatite
of a particle size of from 10 to 50.mu., 4% by weight of magnesium
stearate, 1% by weight of bentonite, 4% by weight of magnesium
myristate, 2% by weight of guaigum, 12% by weight of colour pigment
and 5% by weight of white pigment.
Description
BACKGROUND OF THE INVENTION
The present invention relates generally to a cosmetic stick for
forming a powder stick or pencil, for directly applying powder to
the skin.
One form of cosmetic stick is disclosed in German laid open
application (DE-OS) No. 31 03 128, corresponding to U.S. Ser. No.
325,493; the cosmetic stick comprises a shaped body which is formed
from powder base materials and pigments, possibly with the addition
of binding agent, lubricant and/or adhesion-enhancing agent. In
addition to the base materials, pigments and other additives which
normally go to make up a powder pencil, the above-indicated
cosmetic stick also includes a particulate material which is
present in finely divided form and the particles of which are
harder than all the other base materials. The aim and purpose of
the additional particulate material is to prevent the surface of
the powder stick or pencil becoming clogged with grease or moisture
when the powder pencil is rubbed against the skin to apply powder
thereto. In comparison with using powder from powder compacts,
which is applied by means of an applicator, applying powder by
directly rubbing the surface of the powder pencil against the skin
has the advantage that it is easier to do and is more hygienic.
However, the fact that the surface of the powder pencil becomes
clogged, which may even occur in some cases after relatively short
periods of use, is found to be an extremely troublesome aspect
insofar as the surface of the powder stick becomes solid and glossy
or glazed as a result of such clogging by such grease and moisture,
so that it no longer deposits any powder on the skin of the person
using the powder pencil, hence giving rise to the necessity for
fresh powder to be exposed by for example making a fresh point on
the powder pencil. The above-mentioned harder particulate material
effectively prevents or at least reduces such clogging.
In the known cosmetic stick, the particulate material comprises
quartz flour or substances derived from silicon dioxide, for
example pumice powder and it is present in a proportion of 20 to
40% by weight, with a particle size of between 10 and 100.mu.. In
that connection, a comparatively high proportion by weight of
crystalline quartz can be considered to be a disadvantage from
physiological points of view; in addition, those natural substances
have a comparatively wide range of particle sizes so that expensive
sifting operations have to be carried out after the grinding or
crushing operation, in order to produce an at least relatively
uniform particle size. Finally, additional cost is involved in
avoiding contamination by other substances, possibly also including
heavy metals which may be present, depending on the region in which
the naturally occurring raw materials were mined.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an improved
cosmetic stick for a powder pencil, which is more resistant to
clogging by grease or moisture.
Another object of the present invention is to provide a cosmetic
stick which includes particulate material which is physiologically
acceptable, in a small proportion by weight.
Still another object of the present invention is to provide a
cosmetic stick for a powder pencil, which is easy to produce by
virtue of the nature of the materials employed therein.
A still further object of the present invention is to provide a
cosmetic stick including a particulate material of at least
substantially regular particle size, while being readily
manufacturable.
According to the present invention, these and other objects are
achieved by a cosmetic stick for a powder pencil, comprising a
stable or rigid stick body which is produced for example by
compacting or extruding or otherwise putting into a stable stick
form, powder base material and pigment, optionally with a binding
agent, a lubricant and/or an adhesion-enhancing agent, together
with a particulate material which is contained in finely divided
form in addition to the base materials. The particles of the
particulate material are of greater hardness than the base
materials. The particulate material includes one or more
derivatives of tricalcium phosphate, tetracalcium phosphate or
calcium pyrophosphate.
Tricalcium phosphate and the above-mentioned derivatives thereof
may be produced in a narrow range of particle sizes, for example by
sintering and subsequent crushing or grinding. As therefore a
larger proportion of the particles in a given amount of the
particulate material is of a uniform size, a larger proportion
thereof is also effective in accordance with the invention in the
cosmetic pencil, thereby in turn affording the possibility of a
smaller amount of the additive material being used in the cosmetic
stick. It has been found that the proportion by weight of
particulate material in the cosmetic stick can be reduced to around
5%.
The use of derivatives of tricalcium phosphate is further based on
the realisation that that material is completely acceptable and
harmless from the physiological point of view and moreover can be
manufactured in a narrow particle size range, without a
particularly high level of technical expenditure being involved.
Such derivatives, for example calcium dihydrogenphosphate, are in
part already known as cleaning and polishing agents in regard to
dental care.
Tricalcium phosphate or a derivative thereof is used in the
cosmetic pencil, with a particle size of from 10 to 50.mu.. After a
crushing or grinding operation, the particles have the desired
irregular and rough surface.
Tricalcium phosphate or derivatives thereof may be obtained from
the various naturally occurring apatite minerals which have a MOHS
hardness of around 5. Those materials are ground or crushed and
then subsequently sifted or sieved in order to give the particle
size of from 10 to 50.mu. which is required for the particulate
material to be used in the cosmetic stick.
However, it is also possible for the phosphate of the particulate
material to be produced by sintering hydroxylapatite (formula:
Ca.sub.5 (PO.sub.4).sub.3 OH), thereby achieving a further
improvement in that the expenditure involved in regard to the
crushing and sifting operations is reduced, while nonetheless still
making it possible to produce a substantially uniform grain
size.
The material which is synthetically manufactured in that way
essentially comprises tricalcium phosphate. The manufacturing
process generally involves operating in such a way that the
hydroxyapatite, with a grain size of about 1 to 2.mu. resulting
from the method of production thereof, is subjected to a melting
and calcination process at about 1300.degree. C., with the addition
of calcium pyrophosphate (formula: Ca.sub.2 P.sub.2 O.sub.7); when
a molten phase occurs, depending on temperature, substantially
complete conversion to tricalcium phosphate (Ca.sub.3
(PO.sub.4).sub.2) occurs. In that connection, besides an increase
in grain size, there is also a structural change in which the
individual crystallites grow together to form larger bodies with a
porous structure. Such bodies can be obtained by the sintering
operation, with a range of grain sizes from which, by means of
sifting and possibly a crushing or grinding operation before that,
they can be used directly in a cosmetic stick for the purposes in
question.
Particles which are produced in that fashion are particularly
suitable if they have a controlled porosity of about 0.5 to 1.5.mu.
diameter. That may be achieved by adding hydroperoxide in the
sintering operation, and maintaining a suitable temperature
control.
However, it is also possible to provide for reaction sintering over
several hours, by admixing calcium pyrophosphate. That mode of
operation produces a virtually pore-free material which can be
subsequently broken up, sieved or sifted in order thereby to give
the desired grain size distribution. In this respect also the
expenditure is considerably lower in comparison with the process
which involves dealing with natural apatite because, after the
sintering operation, the phosphate is already available with a
better grain size distribution.
The operation of sintering hydroxylapatite in order to produce
tricalcium phosphate is known per se and described in the
literature (see for example: `Neuere Ingenieur-Technik`, 47th
edition 1975, No. 8; H. Heide, K. Koster, H. Lukas, `Gesinterte
Hydroxylapatit als Biokeramin`; J. G. J. Deelen, Phillips
Technische Rundschau 37, No. 9/10, 255-257, 1977/78, and
`Preparation and Properties of sintered Hydroxylapatit`/Ceramurgia
International, vol 4 No. 2 1978. There is therefore no need at this
point to go into details in regard to manufacture thereof, the
foregoing references being incorporated herein. As can be seen from
the two-component system Ca/P (see E. M. Levin, C. R. Robins, H. F.
MacMurdy; Phase-Diagrams for Ceramists, The American Ceramic
Society (1964), FIG. 246-System CaO-P.sub.2 O.sub.5 ; page 107), in
the range of 47 to 54% by weight of calcium oxide components, it is
still possible to achieve substances which can be satisfactorily
melted and which thus can also be sintered and which may be
compressed to form both porous bodies and also compact
material.
Further objects, features and advantages of the present invention
will be more clearly apparent from the following description of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1a and 1b are diagrammatic views in longitudinal section of
two known forms of powder pencil, incorporating a cosmetic stick
constructed in accordance with the principles of this invention,
and
FIGS. 2 through 4 show highly enlarged representations of
hydroxylapatite which is used in the cosmetic stick according to
the invention, in various conditions of treatment.
DESCRIPTION OF PREFERRED EMBODIMENTS
Reference will first be made to FIG. 1a showing a powder pencil
which essentially comprises a cosmetic stick 1 and a container 2
which comprises metal or plastic material and in which a screw
sleeve or tube 3 is accommodated. The stick 1 may be pushed out in
known fashion by relative rotary movement of the screw sleeve 3
with respect to the container 2 so that the front end surface 4 of
the stick 1 can be applied to the skin of the person using the
powder pencil, whereby powder can be applied to the skin of that
person by rubbing the stick thereover.
FIG. 1b shows another form of powder pencil in which the stick 1'
is accommodated in a shank portion 5 comprising for example wood or
plastic material which can be formed into a point in suitable
fashion, so that after the tip of the stick 1' has been used up, a
fresh point can be exposed thereon again by sharpening the member
5.
It will be appreciated that the external appearance of the powder
pencils shown in FIGS. 1a and 1b is no different from those of
known powder pencils or like cosmetic sticks. However, the makeup
of the cosmetic stick 1 or 1' of the respective powder pencils is
in accordance with the principles of this invention.
Reference will therefore now be made to accompanying FIGS. 2
through 4 are draftsman's representations showing hydroxylapatiteas
an appropriate starting material prior to the sintering operation
with a grain size of between 1 and 2.mu. (with reference to FIG. 2;
insofar as particles of larger size can be seen, they are
agglomerates, which are only lightly bound together, of the smaller
particles). FIG. 3 shows a particle having a porous structure,
which was produced by growing together of the individual
crystallites in the sintering operation, while FIG. 4 shows
particles as a result of the above-mentioned reaction sintering
operation, which are virtually pore-free and which have been broken
down to the required grain size.
Incorporating the tricalcium phosphate into the basic material for
producing the cosmetic stick in accordance with the principle of
this invention does not require any special process steps. In a
suitable form of process, all the powder components including the
tricalcium phosphate which is to be added in accordance with the
invention are intimately mixed together so as to ensure that all
the components are homogeneously distributed intimately with each
other. After that, added to the resulting powder mix is an aqueous
binding agent and the resulting kneadable material is kneaded again
for the purposes of complete homogenisation thereof. The material
is formed into a stable stick body by any suitable form of
operation, preferably by extrusion, which is then followed by a
drying operation for removing water, thereby to produce the stable
stick body. The respective amounts of water added depend on the
nature of the water-soluble binding agent used, these being factors
of which the man skilled in the art will be aware so that there is
no need for detailed consideration of those aspects herein.
In accordance with an embodiment of a cosmetic stick according to
the present invention, the following substances are mixed together
and processed, in accordance with the procedure outlined above:
22% by weight of talcum and 35% by weight of mica as base material
(filling substances), 15% by weight of sintered hydroxylapatite
which is crushed down to a particle size of from 10 to 50.mu. and
which is of a structure as shown in FIG. 3, 4% by weight of
magnesium stearate as a lubricant, 1% by weight of bentonite and 4%
by weight of magnesium myristate as adhesio-enhancing agent, 2% by
weight of guargum, 12% by weight of colour pigment and 5% by weight
of white pigment, for example titanium dioxide.
As noted above, it has been found that it is possible for the
proportion by weight of particulate material in the cosmetic stick
to be reduced to about 5%, with the component of particulate
material preferably being contained in the stick in a proportion of
from about 5 to 40% by weight, with a further preferred proportion
thereof being from about 7 to 20% by weight. Also as indicated
above, the additional particulate material in accordance with this
invention ensures that clogging of the surface of the cosmetic
stick by grease and/or moisture from the skin when the powder of
the stick is being directly applied thereto is at least
substantially reduced by the stick composition according to the
invention.
It will be further appreciated that the above-described embodiment
of a stick in accordance with this invention is described solely by
way of example thereof and that further alterations and
modifications may be made therein without thereby departing from
the spirit and scope of the invention.
* * * * *